COLOMBO, Sri Lanka — Police in Sri Lanka said Monday the investigation into the Easter Sunday bombings will examine reports that the intelligence community failed to detect or warn of possible suicide attacks before the violence.

The nine bombings of churches, luxury hotels and other sites was Sri Lanka's deadliest violence since a devastating civil war in the South Asian island nation ended a decade ago. Police spokesman Ruwan Gunasekara said Monday the death toll had risen overnight to 290 dead with more than 500 wounded.

Two government ministers have alluded to intelligence failures. Telecommunications Minister Harin Fernando tweeted, "Some intelligence officers were aware of this incidence. Therefore there was a delay in action. Serious action needs to be taken as to why this warning was ignored." He said his father had heard of the possibility of an attack as well and had warned him not to enter popular churches.

And Mano Ganeshan, the minister for national integration, said the security officers within his ministry had been warned by their division about the possibility two suicide bombers would target politicians.

Gunasekara said the Criminal Investigation Department investigating the blasts will look into the reports.

Defense Minister Ruwan Wijewardena previously described the blasts as a terrorist attack by religious extremists, and police said 13 suspects were arrested, though there was no immediate claim of responsibility. Wijewardena said most of the bombings were believed to have been suicide attacks.

The explosions — mostly in or around Colombo, the capital — collapsed ceilings and blew out windows, killing worshippers and hotel guests in one scene after another of smoke, soot, blood, broken glass, screams and wailing alarms. Victims were carried out of blood-spattered pews.

"People were being dragged out," said Bhanuka Harischandra, of Colombo, a 24-year-old founder of a tech marketing company who was going to the Shangri-La Hotel for a meeting when it was bombed. "People didn't know what was going on. It was panic mode."

He added: "There was blood everywhere."

Most of those killed were Sri Lankans. But the three bombed hotels and one of the churches, St. Anthony's Shrine, are frequented by foreign tourists, and Sri Lanka's Foreign Ministry said the bodies of at least 27 foreigners from a variety of countries were recovered.

The U.S. said "several" Americans were among the dead, while Britain, India, China, Japan and Portugal said they, too, lost citizens.

The streets were largely deserted Monday morning, with most shops closed and a heavy deployment of soldiers and police. Stunned clergy and onlookers gathered at St. Anthony's Shrine, looking past the soldiers to the stricken church.

The Sri Lankan government lifted a curfew that had been imposed during the night. But most social media remained blocked Monday after officials said they needed to curtail the spread of false information and ease tension in the country of about 21 million people.

Prime Minister Ranil Wickremesinghe said he feared the massacre could trigger instability in Sri Lanka, and he vowed to "vest all necessary powers with the defense forces" to take action against those responsible.

The Archbishop of Colombo, Cardinal Malcolm Ranjith, called on Sri Lanka's government to "mercilessly" punish those responsible "because only animals can behave like that."

The scale of the bloodshed recalled the worst days of Sri Lanka's 26-year civil war, in which the Tamil Tigers, a rebel group from the ethnic Tamil minority, sought independence from the Buddhist-majority country. The Tamils are Hindu, Muslim and Christian.

Sri Lanka, off the southern tip of India, is about 70 percent Buddhist. Scattered incidents of anti-Christian harassment have occurred in recent years, but nothing on the scale of what happened Sunday.

There is also no history of violent Muslim militants in Sri Lanka. However, tensions have been running high more recently between hard-line Buddhist monks and Muslims.

Two Muslim groups in Sri Lanka condemned the church attacks, as did countries around the world, and Pope Francis expressed condolences at the end of his traditional Easter Sunday blessing in Rome.

"I want to express my loving closeness to the Christian community, targeted while they were gathered in prayer, and all the victims of such cruel violence," Francis said.

Six nearly simultaneous blasts took place in the morning at the shrine and the Cinnamon Grand, Shangri-La and Kingsbury hotels in Colombo, as well as at two churches outside Colombo, according to a Sri Lankan military spokesman, Brig. Sumith Atapattu.

A few hours later, two more blasts occurred just outside Colombo, one of them at a guesthouse, where two people were killed, the other near an overpass, Atapattu said.

Also, three police officers were killed during a search at a suspected safe house on the outskirts of Colombo when its occupants apparently detonated explosives to prevent arrest, authorities said.

The Shangri-La's second-floor restaurant was gutted, with the ceiling and windows blown out. Loose wires hung down and tables were overturned in the blackened space. From outside the police cordon, three bodies could be seen covered in white sheets.

Sri Lankan forces defeated the Tamil Tiger rebels in 2009, ending a civil war that took over 100,000 lives, with both sides accused of grave human rights violations.

Harischandra, who witnessed the attack at the Shangri-La Hotel, said there was "a lot of tension" after the bombings, but added: "We've been through these kinds of situations before."

He said Sri Lankans are "an amazing bunch" and noted that his social media feed was flooded with photos of people standing in long lines to give blood.